Women's entrepreneurship is central to the functioning of agri-food systems in sub-Saharan Africa, yet women-owned enterprises remain constrained by socio-cultural, structural, and financial barriers. This study examines how open-market systems shape opportunities and constraints for women entrepreneurs in agri-food businesses in Thyolo and Chiradzulu districts of Malawi. Rather than assuming linear enterprise progression, the analysis considers observable differences in enterprise scale, capitalization, and market integration. Using a mixed-methods design, data were collected from 360 women entrepreneurs through surveys, interviews, and field observations. Findings indicate that most enterprises operate at micro scale with low start-up capital, limited reinvestment, and minimal formalization, reflecting necessity-driven entrepreneurship. Open markets provide accessible spaces for income generation and household resilience, but also expose women to financial exclusion, weak institutional support, and gendered vulnerabilities. Capacity gaps are substantial, with limited access to business training despite strong demand for financial, marketing, and processing skills. Climatic shocks, governance weaknesses, and infrastructural deficits further constrain enterprise stability. Despite these challenges, women demonstrate pragmatic financial aspirations and engagement in collective arrangements, revealing latent growth potential. The study highlights the importance of gender-responsive finance, practical skills development, stronger group governance, and climate-resilient market infrastructure for improving enterprise sustainability and productivity in informal agri-food systems.